Cleft sign can be used to distinguish an extra axial lesion from an intra axial lesion and is typically used in the description of a meningioma.
Classically, the cleft was regarded as representing a thin rim of CSF between tumour and brain parencyma. However, it often is of high signal on FLAIR imaging and most likely represents a non-CSF tumour-brain interface.
Nevertheless, it remains a good sign that a mass is extraaxial and is typically made up of:
- high T2 signal: (?) CSF (?) other
- vessels: pial or as in case 1, larger vessels.
- hypointense dura (on both T1 and T2 on the surface of the mass (if extra dural)
- imaging signs
- by location
- primary dural lymphoma
- Rosai-Dorfman disease
- solitary fibrous tumour of the dura
- EBV-associated smooth muscle tumour
- meningeal melanocytoma
- primary meningeal malignant melanoma
- Erdheim-Chester disease
Synonyms & Alternative Spellings
|Synonyms or Alternative Spelling||Include in Listings?|
|CSF cleft sign||✗|